I've
said it before on this list, so I will simply reference the previous
discussion(s) and say here that Piranha solution is exceedingly
dangerous and, in all but carefully controlled and highly limited
circumstances, poses an unacceptable risk in synthetic research
labs. The near miss you describe and the apparently limited
knowledge of those who were using it serves to reinforce my
argument.

I have been reading about how to make Piranha solution and I keep
coming across this statement, “Add the acid to the peroxide,
although some authorities disagree” Why would
authorities not agree that adding acid to water instead of water to acid
is best?

I have seen some say add acid to peroxide for initial solution,
butwhen
refreshing, add aliquots of hydrogen peroxide to Piranha
mixture. Is that ok?

We recently had an incident when Piranha came in contact with ferric
chloride and instantly reacted

violently Was this due to the metal, the fact that both are oxidizers,
both, or something else?

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